Section 5 declaration or Class 3A notification?

A Section 5 declaration and a Class 3A notification serve different purposes. The declaration asks the planning authority to decide an exemption question about described works. The notification records reliance on the Class 3A exemption. Neither name should be used as shorthand for the separate Building Control process.

What does a Section 5 declaration cover?

A Section 5 declaration answers whether the development described in a request is or is not exempted development. The request goes to the relevant planning authority with the information needed to decide that question. Planning and Development Act 2000, Section 5.

Dublin City Council’s Section 5 form asks for the subject site, details of the works and a list of supporting plans or drawings. Its assessment covers only the works listed and described in that application. Dublin City Council Section 5 application form.

Before preparing a request, agree precisely what question you want answered. Keep the proposed use, drawings and description consistent. Ask your planning adviser whether a Section 5 request is appropriate for the uncertainty in your case, rather than submitting one simply because a supplier mentions an exemption.

What does the Class 3A notification do?

Conditions 16–18 require notification to the planning authority at least 14 days before work starts; the notification records use of the exemption and is not planning approval. S.I. No. 340/2026, Class 3A.

That distinction matters when planning the work: do not describe a notification as an approval or treat a receipt as confirmation that the site satisfies every condition. Discuss the complete proposal against the Class 3A conditions and resolve missing information before relying on the exemption.

Where does Building Control fit?

A Class 3A auxiliary dwelling follows the normal Building Control process, including a Commencement Notice, design and assigned certifiers, a competent builder and a Certificate of Compliance on Completion. Department Circular BC07-2026.

Keep a separate line for Building Control in the project programme. Ask who handles the professional appointments, submission and completion documents. Our BCMS and Class 3A guide explains the two pre-start processes; the paperwork guide links the council material.

Which site details should you prepare?

Condition 7 of Class 3A sets a 32–45 m² external-footprint band, counted together with earlier Class 3 garden structures. S.I. No. 340/2026, Class 3A.

Bring a measured site layout and details of existing garden structures to the discussion. Ask your adviser to assess the whole proposal, including use, access, services and remaining garden. Do not treat the area band as a complete eligibility test.

Keep one document list with the current drawing revision, the works described, the intended use and any unresolved question. If the design changes, ask whether the planning advice and proposed submissions need updating. Avoid carrying an old decision or an unrelated supplier example into a different proposal.

What should you do before paying for the build?

• Describe the proposed development and intended use consistently.
• Identify the specific uncertainty that needs planning advice.
• Agree which planning and Building Control documents are required.
• Allocate responsibility for preparing, signing and lodging each document.
• Keep unresolved matters visible before ordering site work.

For a permanent Nua Living garden home, compare the dwelling options and request a callback and free site visit. Use that discussion to clarify the proposal and the next professional checks, not as a substitute for a site-specific planning determination.